Grant Hartwig

Grant Alexander Hartwig (born December 18, 1997) is an American professional baseball pitcher who is a free agent. He has previously played in Major League Baseball (MLB) for the New York Mets, and in Nippon Professional Baseball (NPB) for the Hanshin Tigers.

Amateur career Hartwig attended Detroit Catholic Central High School in Detroit, Michigan, and played for the school's baseball team. He enrolled at Miami University of Ohio, where he played college baseball for the Miami Redhawks. He underwent Tommy John surgery in April 2018 and missed the rest of the season and the entire 2019 season. The 2020 season was abbreviated due to the COVID-19 pandemic.

During the 2021 season, Hartwig's senior year, no scouts approached him prior to the 2021 Major League Baseball draft. He was not selected in the draft's 20 rounds. Hartwig graduated with a bachelor's degree in microbiology and returned to his parents' house and studied for the Medical College Admission Test (MCAT).

Hartwig started the 2023 season with Syracuse. In 21 appearances for the team, he registered a 4.21 ERA with 35 strikeouts and 3 saves in innings of work. The Mets promoted Hartwig to the major leagues for the first time on June 19, 2023, and he made his major league debut the same day, relieving Max Scherzer in the ninth inning of a game against the Houston Astros. Hartwig pitched one inning, giving up no runs on one hit and one walk. He made 28 appearances for the Mets in his rookie campaign, posting a 5–2 record and a 4.84 ERA with 30 strikeouts across innings pitched.

Hartwig was optioned to Triple–A Syracuse to begin the 2024 season. On June 21, 2024, Hartwig underwent surgery to repair a torn meniscus in his left knee and was ruled out for six–to–eight weeks. Once healthy, he made 4 appearances for the Mets, logging a 6.75 ERA with 4 strikeouts over innings pitched. On November 22, Hartwig was non–tendered by the Mets and became a free agent.

On December 2, 2024, Hartwig re–signed with the Mets on a minor league contract. He made 21 appearances for Triple-A Syracuse, registering a 2-3 record and 3.42 ERA with 33 strikeouts and two saves across innings pitched. On June 27, 2025, Hartwig was released by the Mets organization.

Hanshin Tigers On July 14, 2025, Hartwig signed with the Hanshin Tigers of Nippon Professional Baseball. In 16 appearances for the Tigers, Hartwig logged a 2-0 record and 3.65 ERA with eight strikeouts across innings pitched.

Minnesota Twins On December 2, 2025, Hartwig signed a minor league contract with the Minnesota Twins. In 34 games with Triple-A St. Paul Saints he threw 40 innings of relief going 5-3 with a 6.30 ERA with 38 strikeouts and 4 saves. He was released on August 6, 2026.